<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script type="text/javascript" src="../../js/jquery-1.7.2.js"></script>
    <script type="text/javascript">
        //window.onload 和 $()的区别
        //如果在script代码块中写多个window.onload，只会执行一个
        window.onload = function () {
            alert("window.onload3");
        }
        //如果有多个 $(function () {}); 会依次执行，并且速度比window.onload快
        $(function () {
            alert("jQuery核心函数1");
        });
    </script>
</head>
<body>

<iframe src="https://wwww.hao123.com" width="500px" height="500px"></iframe>
</body>
</html>